RT info:eu-repo/semantics/article
T1 Influence of silica aerogel particles on the foaming process and cellular structure of rigid polyurethane foams
A1 Cimavilla Román, Paula
A1 Pérez Tamarit, Saúl
A1 Santiago Calvo, Mercerdes
A1 Rodríguez Pérez, Miguel Ángel
K1 Polyurethane foams
K1 Espumas de poliuretano
K1 Nanoporous silica aerogels
K1 Aerogeles de sílice nanoporosa
K1 Reaction kinetics
K1 Cinética química
AB Water blown rigid polyurethane (RPU) composite foams were produced using different concentrations of nanoporous silica aerogel micrometric powder (0.5, 1 and 3 wt%). The effect of these particles on the foaming kinetics was analysed from a physical and chemical viewpoint. On the physical side, the foaming process was studied by in-situ X-ray radioscopy. The inclusion of aerogel particles in the system delays the foam expansion and enhances the nucleation of cells. However, high amounts of these particles (3 wt%) lead to intense cell coalesce during foam evolution. On the chemical side, the reaction kinetics was investigated by in-situ FTIR spectroscopy and reaction temperature measurements. The addition of low contents of aerogel (below 3 wt%) reduces the conversion of isocyanate while favouring the generation of urethane groups, which explains the higher density of the foams with low aerogel contents. However, the foam with high contents of aerogel (3 wt%) does not change the reaction balance in comparison to the reference. Therefore, this foam presents similar expansion and density to those of the unfilled foam (Reference). Furthermore, higher reaction temperatures were reached by the reference foam during the foaming process, and higher dissipation speeds of these temperatures were detected for the foams containing aerogel with respect to those of the reference foam.
PB Elsevier
SN 0014-3057
YR 2020
FD 2020
LK https://uvadoc.uva.es/handle/10324/49209
UL https://uvadoc.uva.es/handle/10324/49209
LA eng
NO European Polymer Journal, 2020, vol. 135, 109884
NO Producción Científica
DS UVaDOC
RD 22-nov-2024